I was trying to expose three wafers. The first two made it through without problems. The third wafer disappeared from the status monitor during the move from P chuck to E chuck. When I tried to clear the batch from the tool, it showed up as red on the E chuck. When I tried to reinitialize the wafer handling, it said there was a risk to the wafers due to an unsafe situation and that the wafers would need to be removed manually.
There is a box by the reticle exchange station into which the wafers can be placed.
Sorry.